Folding ramp

ABSTRACT

A folding cargo loading/unloading ramp, particularly adapted for motor trucks, includes first and second ramp sections and an intermediate support leg assembly which is pivotally connected to the first and second ramp sections at a common hinge point. The support leg assembly includes a latch for automatically latching the support leg assembly in a working position when it is rotated from a folded position to its working position, the latch being manually actuatable to unlock the support leg assembly to rotate back to its folded or non-working position. Both ramp sections and the support leg assembly include manipulating handles to facilitate movement of the ramp between a stored position and a working position.

BACKGROUND

In the art of cargo loading and unloading ramps for motor vehicles, suchas delivery trucks, in particular, there is an ever present need forproviding a ramp which is lightweight, durable and easy to manipulatewhen moving the ramp between a stored position on the motor vehicle anda working position for loading or unloading cargo. In order to provide aramp with a sufficiently shallow slope in its working position, foldingramps have been developed wherein the ramp is constructed to have atleast two ramp sections interconnected by a hinge joint. However, whenthis type of ramp is provided, it is necessary to also provideintermediate support structure generally at the hinge joint so that thehingedly interconnected ramp sections are properly supported in theirworking positions.

Moreover, it is also important that the intermediate support structurebe movable to a retracted position out of the way when the ramp is movedto its stored position. However, this support structure must also besuitably latched in its working position to minimize the chance ofcollapse when the ramp is in use. It is to provide the above-mentioneddesiderata in cargo vehicle loading and unloading ramps, as well asother features, that the present invention has been developed.

SUMMARY OF THE INVENTION

The present invention provides an improved loading and unloading rampfor cargo vehicles, such as motor delivery trucks and the like.

In accordance with one aspect of the present invention, a folding cargoloading and unloading ramp is provided which is easily stored in afolded position on the vehicle and may also be easily manipulated by oneor more persons for movement between a stored position and a workingposition. In this respect the ramp of the present invention is oflightweight but durable construction and is provided with an improvedarrangement of handles for moving the ramp between a working and astored position. The ramp of the present invention is also provided withan improved arrangement of rollers, slides and locating bosses forsupporting the ramp for movement between working and stored positionsand for securing the ramp in a working position.

The present invention further provides a folding ramp with an improvedlatch mechanism which automatically latches a support leg assembly whensuch leg assembly is moved to its working position. The latch mechanismis easily manipulated for releasing the support leg assembly formovement when it is desired to move the ramp from a working position toa stored position.

Still further, the present invention provides an improved arrangement ofintermediate support structure which includes telescopically movableinner support legs connected to outer support legs and provided with animproved arrangement of support rollers for contact with supportsurfaces when the ramp is being moved between a working position and astored position. The telescoping inner support legs are provided withopposed sets of rollers for engagement with the ground and withactuating cams to allow the ground engaging rollers to move betweenworking and stored positions.

The above-mentioned features together with other unique aspects of thepresent invention will be further appreciated by those skilled in theart upon reading the detailed description which follows in conjunctionwith the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side elevation of the folding ramp of the present inventionin its folded position for storage in a suitable compartment on a motortruck, for example;

FIG. 2 is a detail side elevation of the folding ramp shown in FIG. 1with the intermediate support leg assembly rotated to a workingposition;

FIG. 3 is a view similar to FIG. 2 showing the lower ramp of the foldingramp rotated to a working position;

FIG. 4 is a view taken generally from the line 4—4 of FIG. 1;

FIG. 5 is a detail view of the ramp intermediate support leg assemblytaken generally from the line 5—5 of FIG. 3;

FIG. 6 is a plan view of the folding ramp in an unfolded, workingposition;

FIG. 7 is a detail section view of the upper ramp section takengenerally from the line 7—7 of FIG. 6;

FIG. 8 is a detail section view taken generally from the line 8—8 ofFIG. 3;

FIG. 9 is an end elevation view of the upper ramp section taken from theend which is hinged to the lower ramp section; and

FIG. 10 is a detail section view of the latch mechanism for theintermediate support leg assembly and is taken generally from the sameline as the view of FIG. 7.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT

In the description which follows like parts are marked throughout thespecification and drawings with the same reference numerals,respectively. The drawing figures are not necessarily to scale.

Referring to FIG. 1, the folding ramp of the present invention isgenerally designated by the numeral 12 and is characterized by aso-called upper ramp section 14 which is hingedly connected to a lowerramp section 16 so that the lower ramp section may be folded to theposition shown in FIG. 1 for storage in a suitable compartment 13 whichmay comprise an open ended rectangular cross section, tubular storagebox on board a motor truck, for example. By way of example a typicalstorage compartment may be a generally tubular box-like structure 13disposed between the longitudinal frame rails of a motor truck chassis.As shown also in FIGS. 2 and 3, the folding ramp 12 is provided with anintermediate support leg assembly, generally designated by the numeral18, which is hingedly connected to the upper and lower ramp sections ata common pivot axis 20, see FIGS. 1 and 8 also.

As shown in FIGS. 8 and 9, for example, the upper ramp section 14 isprovided with spaced apart hinge bracket members 22 which are disposedadjacent spaced apart hinge bracket members 24, FIG. 8. Bracket members24 are connected to the support leg assembly 18 and are also disposedadjacent spaced apart hinge bracket members 26 which are secured to thelower ramp section 16. Each of the hinge brackets 22, 24 and 26 isprovided with a suitable pivot pin bore in which a pivot or hinge pin 28is disposed, as shown in FIG. 8, to provide the common hinge or pivotaxis 20 between the upper and lower ramp sections and the support legassembly.

Accordingly, the folding ramp 12 may be removed from the aforementionedstorage position to a point wherein the leg assembly 18 may be swungfrom the position shown in FIG. 1 to the position shown in FIG. 2followed by the step of swinging the upper ramp section 16 from theposition shown in FIGS. 1 and 2, to the position shown in FIG. 3.

Referring now to FIGS. 6, 7 and 9, the upper ramp section 14 ischaracterized by opposed elongated rail members 32 between which aredisposed side by side perforated deck plates 34 forming the ramp decksurface. The rails 32 may be formed of extruded metal, such as aluminumalloy, for example, and the deck plates 34 may also be fabricated ofstamped, cast, or extruded aluminum plate, for example. The rails 32, asshown in FIG. 9, have opposed curved flanges 32 a and 32 b and arecessed web 32 c for receiving the side edges of the deck plates 34,respectively, as shown. The deck plates 34 may be secured to the rails32 by welding or by mechanical fasteners.

The upper end of the ramp section 14 is provided with a fixed,plate-like lip member 38 which includes opposed side edge flanges 38 asecured to the opposed rails 32 by welding, for example. The lip 38 isprovided with spaced apart, depending, ramp locating bosses 40 which maybe disposed in corresponding boss receiving holes 41 a in a vehicle loaddeck 41, see FIG. 7, for securing the upper end of the ramp 12 in aworking position. Bosses 40 may comprise plastic threaded nut memberssecured respectively to threaded round head screws 40 a, FIGS. 6 and 7.A suitable tread plate 39, including spaced apart antiskid tread members39 a, may be interposed the lip 38 and the first deck plate 34, as shownin FIGS. 6 and 7. Tread plate 39 may be secured to the rails 32 in thesame manner as the deck plates 34.

As shown in FIGS. 7 and 9, the upper ramp section 14 is also providedwith spaced apart support rollers 42 which are rotatably supported onramp section 14 adjacent its upper end by suitable channel shapedbrackets 44. The brackets 44 are suitably secured to respective ones ofthe rails 32, as shown in FIGS. 7 and 9. By locating the support rollers42 adjacent the upper end of the upper ramp section 14, movement of theramp 12 into and out of its storage position is facilitated.

Referring further to FIGS. 6 and 9, the upper ramp section 14 is alsoprovided with a first pair of opposed ramp manipulating handles 46disposed adjacent the upper end of the upper ramp section and secured,respectively, to respective ones of the rails 32. The location of thehandles 46 together with other manipulating handles to be describedfurther herein is advantageous for manipulating the ramp 12 when movingthe ramp between working and stored positions. As further shown in FIG.9, the hinge brackets 22 for the ramp section 14 each include a bossportion 22 a which fits between the flanges 32 a and 32 b of the siderails 32. The hinge brackets 22 are suitably releasably secured to theside rails 32 by conventional threaded fastener assemblies 23, FIG. 9,but may also be welded to the side rails.

Referring again to FIG. 7, the upper ramp section 14 includes a latchcatch member 50 mounted on the underside of one of the deck plates 34comprising the end deck plate at the end of the ramp section 14 oppositethe lip 38. Catch 50 is preferably centered between rails 32. Thepurpose of the catch 50 will be described in further detail herein.

Referring further to FIGS. 6 and 8, the lower ramp section 16 is alsocharacterized by opposed elongated rail members 52 substantially likethe rail members 32 but generally of shorter length and includingopposed flanges 52 a and 52 b with an intermediate web part 52 c havinga channel formed therein, as shown in FIG. 8, for receiving oppositeends of side by side deck plates 34. The deck plates 34 of the rampsection 16 are secured to the rails 52 in the same manner as adjacentside by side deck plates 34 are secured to the rails 32. The lower rampsection 16 is also provided with opposed generally fin-like slidemembers 56 which are secured to the rails 52 by suitable threadedfastener assemblies 58, as shown in FIG. 8, as well as FIG. 1. Thereplaceable slides 56 are preferably formed of a plastic, such aspolypropylene, and are operable to engage the top wall 13 a, FIGS. 1 and4, of box or compartment 13 when the ramp 12 is being moved into or outof such box and to facilitate such movement. Thanks to the provision ofthe slides 56 of a material such as polypropylene, the slides providejust enough frictional resistance as they engage wall 13 a to allow easeof management of the ramp as it is moved in and out of enclosure 13.Slides 56 are also dimensioned such as to engage top wall 13 a withoutallowing ramp 12 to tilt excessively with respect to enclosure 13 as itis moved in or out of such enclosure.

As further shown in FIGS. 6 and 8, the opposed hinge brackets 26 for theramp section 16 are releasably secured to the rails 52 by suitablethreaded fastener assemblies 27 and are spaced from the rails 52 bysuitable spacer members 59. Fasteners 27 also secure opposed cam plates60 to the side rails 52. Cam plates 60 are disposed for engagement withtelescoping members of the leg assembly 18 as will be described furtherherein. As further shown in FIGS. 6 and 8, the lower ramp section 16 hasa distal lip member comprising an antiskid plate 39 b disposed betweenand secured to the rails 52. The lower ramp section 16 further includesa second set of opposed handles 46 secured to the outside surfaces ofthe opposed rails 52 in the same manner that the first mentioned handles46 are secured to the rails 32 of ramp section 14.

Referring now primarily to FIGS. 4 and 5, the intermediate support legassembly 18 is characterized by two spaced apart, elongated, generallyrectangular tube-like support leg members 64 which are interconnected byframe members 66 and 68. Within each support member 64 is disposed anelongated telescopically moveable tubular support leg 70 which includesrollers 72 a and 72 b suitably supported thereon at opposite endsthereof. Each support leg 70 is also preferably characterized as arectangular cross section tubular member and is disposed within atubular leg member 64 for sliding movement over a limited distance asdetermined by two spaced apart support pins 73 which are secured to theleg member 64, respectively, and extend through elongated slots 74formed in the respective tubular leg members 70. Accordingly, thetubular leg members 70 are disposed for limited sliding or telescopingmovement within the leg members 64 between the position shown in FIGS. 3and 5 and the position shown in FIG. 2. In fact, the leg members 70 aremoved into the position shown in FIG. 2 relative to the leg members 64by engagement of rollers 72 a, respectively, with the respective cammembers 60 supported on the ramp section 16 adjacent the end whichsupports the hinge brackets 26.

Accordingly, when the ramp 12 is withdrawn from its storage position,initially, the leg assembly 18 is rotated from the position shown inFIG. 1 to the position shown in FIG. 2. When this action takes place therollers 72 a engage the respective cams 60 forcing the leg members 70 toextend downward relative to the leg members 64 so that rollers 72 bengage the ground G, as shown in FIG. 2. However, when the ramp section16 is rotated from the position shown in FIG. 2 to the position shown inFIG. 3, the cams 60 move out of engagement with rollers 72 a and theweight of the ramp 12 causes the leg members 64 to move downwardrelative to the leg members 70 so that the lower distal ends of the legmembers 64 engage the ground G and rollers 72 b are retracted upwardlywithin the leg members 64, as shown in FIGS. 3 and 5.

Referring further to FIGS. 4 and 5, the support leg assembly 18advantageously includes spaced apart ramp manipulating handles 80 whichare supported on the frame member 68, as shown. In the folded conditionof the ramp assembly 12, as shown in FIG. 1, the handles 80 face aperson addressing the folded ramp 12 and are readily accessible forpulling the ramp 12 out of its boxlike compartment or enclosure 13 orreturning the ramp to the enclosure.

Still further, as shown in FIGS. 4, 5 and 10, the folding ramp 12 of thepresent invention includes an improved latch mechanism for latching theintermediate support leg assembly 18 in the working position shown inFIGS. 2 and 3. The latch mechanism includes a latch member 82 which ispivotally mounted on a support bracket 84 supported on frame member 68generally midway between legs 64. Support bracket 84 comprises agenerally rectangular tube shaped member which is suitably mounted onframe member 68 and supports a pivot pin 86, FIG. 10, for supporting thelatch member 82 for pivotal movement thereabout and on bracket 84. Atorsion coil spring 88, FIG. 10, is supported on pin 86 and includes afirst arm 88 a engaged with latch member 82 and a second arm 88 bengaged with support bracket 84, as illustrated in FIG. 10. Latch member82 includes a hook part 82 a disposed on one side of pivot pin 86 and ahandle part 82 b disposed opposite the hook part and which may bemanually grasped to pivot the latch member 82 about the pin 86 againstthe bias of spring 88.

Accordingly, when the leg assembly 18 is rotated to the position shownin FIGS. 2, 3 and 10, latch member 82 is biased by spring 88 toautomatically engage catch 50 as the leg assembly is swung into theposition shown in FIGS. 2, 3 and 10. However, when it is desired torotate the support leg assembly 18 from the position shown in FIG. 2back to the position shown in FIG. 1, the latch member 82 may be graspedat the handle part 82 b and rotated against the bias of spring 88 (in acounterclockwise direction, viewing FIG. 10) so that the hook part 82 awill move clear of the catch 50 as the leg assembly is rotated to theposition shown in FIG. 1.

Operation of the ramp 12 is believed to be readily understandable fromthe foregoing description. However, briefly, the ramp 12 may be removedfrom its storage compartment or enclosure 13 by grasping one or more ofthe handles 80 and sliding the ramp, in its folded position, partiallyfrom the compartment until the leg assembly 18 may be rotated to itsworking position. Movement of the ramp assembly in and out of thecompartment 13 is facilitated by the rollers 42 and slide members 56.Prior to removing the ramp 12 completely from the compartment 13, andwhile the ramp remains supported in the compartment, the leg assembly 18is rotated to the position shown in FIG. 2 so that the rollers 72 b areoperable to support the ramp when it is removed substantially from thecompartment.

Once the ramp 12 is at least partially removed from the compartment 13,the handles 80 and/or the handles 46 may be grasped to further assist inmoving the ramp. When the leg assembly 18 is rotated to the position ofFIG. 2, the latch 82 automatically engages catch 50 to lock the legassembly in the position of FIG. 2 to prevent inadvertent rotation whichwould possibly result in the ramp collapsing or falling to the ground G.Opposed stop members 85 are mounted on frame member 68, FIGS. 4 and 5,and are engageable with flanges 32 b of rails 32, FIG. 10, to limitmovement of leg assembly 18 to the working position shown. Once the legassembly 18 is in a ramp supporting position, the ramp 12 may be movedfurther from the compartment 13 until the lip 38 rests on the edge ofthe compartment or the upwardmost end of the ramp section 14 rests onthe compartment. The ramp operator may then lift the upper end of theramp section 14 to position it on the load bed 41, generally in theposition as shown in FIG. 7, for example, with bosses 41 disposed in thecooperating receiving bores 41 a, one shown in FIG. 7. Alternatively,the uppermost end 14 a, FIG. 7, of the ramp section 14 may simply reston the load deck 41 if a working angle of the ramp is such as to allowthe lip 38 to essentially be flush with the surface of the load deck.

After positioning the ramp 12 as just described, the ramp section 16 maybe rotated from the position shown in FIGS. 1 and 2 to the positionshown in FIG. 3 by grasping one of the handles 46 on ramp section 16,for example. The handles 46 are preferably placed approximately sixtypercent of the length of the ramp section 16 from the hinge pivot axis20 between the ramp section 16 and the ramp section 14. As the rampsection 16 is moved to the position shown in FIG. 3, the cams 60 moveaway from the rollers 72 a allowing the support leg members 70 to movetelescopically upward with respect to the support leg members 64 wherebythe support leg members 64 then move into engagement with the ground Gas shown in FIG. 3. The ramp 12 is now ready for use for loading and/orunloading cargo with respect to the load deck 41.

When it is desired to replace the ramp 12 within compartment 13, theprocess just described is essentially reversed, that is, the rampsection 16 is folded back to the position shown in FIG. 1 or 2 and theupper end of ramp section 14 is placed partially back in the compartmentor enclosure 13 preferably to a point wherein the slides 56 are operableto engage top wall 13 a and prevent the ramp from falling to the groundG when the leg assembly 18 is folded back to its storage position. Thelatch handle part 82 b is then grasped by the ramp operator to rotatethe latch 82 out of its locking position with respect to the catch 50,at which time the leg assembly 18 may be rotated back to the positionshown in FIG. 1. Prior to unlocking the leg assembly 18 from its workingposition shown in FIGS. 2 and 3, the upper end of the ramp section 14may be, as described, at least partially positioned back within thestorage compartment 13 so that the ramp 12 is supported within thestorage compartment prior to retraction of the leg assembly 18 to itsnon-working position, as shown in FIG. 1. The latch 82 is advantageouslycentered between opposite sides of the ramp 12 so that it may be graspedfrom either side of the ramp during operation to fold the leg assemblyto its storage position.

The construction of the ramp 12 is believed to be within the purview ofone skilled in the art based on the foregoing description and thedrawings. Conventional engineering materials may be used to constructthe various parts of the ramp 12 and which are known to those skilled inthe art of cargo loading and unloading ramps.

Although a preferred embodiment of the invention has been described indetail herein, those skilled in the art will recognize that varioussubstitutions and modifications may be made without departing from thescope and spirit of the appended claims.

1. A portable cargo loading/unloading ramp for freight trucks and thelike comprising: a first ramp section; a second ramp section hingedlyconnected to said first ramp section; a support leg assembly hingedlyconnected to at least one of the ramp sections and adapted to be movedbetween working and non-working positions of said ramp; and a latchmechanism disposed on said support leg assembly and including a latchmember mounted for pivotal movement about a pivot pin for engagementwith a catch mounted on said first ramp section for locking said legassembly in a working position, said latch member including a hook partdisposed on one side of said pivot pin, a handle part mounted on anopposite side of said pivot pin and spring means for biasing said latchmember into engagement with said catch, and said latch member isresponsive to manipulation by an operator of said ramp to move to aposition for unlatching said support leg assembly for rotation to astored position.
 2. The ramp set forth in claim 1 including: supportrollers mounted on said first ramp section adjacent an end of said firstramp section opposite an end which is hingedly connected to said secondramp section.
 3. The ramp set forth in claim 1 including: at least onemanipulating handle disposed on said support leg assembly for graspingby an operator of said ramp to move said ramp between a stored positionand a working position.
 4. The ramp set forth in claim 1 including: atleast one manipulating handle disposed on said second ramp section forgrasping by an operator of said ramp for moving said second ramp sectionbetween a folded position and a working position with respect to saidfirst ramp section.
 5. The ramp set forth in claim 1 including: at leastone manipulating handle supported on said first ramp section adjacent anend of said first ramp section opposite an end which is hingedlyconnected to said second ramp section for manipulating said first rampsection to move between a stored position and a working position.
 6. Theramp set forth in claim 5 wherein: said first ramp section includesmanipulating handles mounted opposite each other on opposite sides ofsaid first ramp section.
 7. The ramp set forth in claim 1 wherein: atleast one of said ramp sections is formed by spaced apart, elongated,substantially parallel support rails and a plurality of deck platesdisposed between said rails and secured thereto, respectively, to formsaid at least one ramp section.
 8. The ramp set forth in claim 7wherein: said rails comprise opposed flanges, a web and a channel formedin said web for receiving opposite sides of said deck plates.
 9. Theramp set forth in claim 8 wherein: said flanges of said rails are formedto have a continuous curved shape to facilitate manipulating said rampby operating personnel.
 10. The ramp set forth in claim 1 wherein: saidsupport leg assembly includes two spaced apart first support leg membersinterconnected to each other, second support leg members operablyconnected to said first support leg members for movement relativethereto and roller means mounted on opposite ends of said second supportleg members, said roller means on one end of said second support legmembers being engageable with the ground for supporting said ramp andother of said roller means being supported on the opposite end of saidsecond support leg members and engageable with cam means on said secondramp section for causing said second support leg members to move withrespect to said first support leg members, respectively, to support saidramp by said roller means.
 11. The ramp set forth in claim 1 including:ramp locating bosses disposed on said first ramp section adjacent oneend thereof.
 12. A portable cargo loading/unloading ramp for freighttrucks and the like comprising: a first ramp section; a second rampsection hingedly connected to said first ramp section; and a support legassembly hingedly connected to at least one of said ramp sections andadapted to be moved between working and non-working positions of saidramp, said support leg assembly includes two spaced apart first tubularsupport leg members interconnected to each other, second tubular supportleg members slidably disposed in said first support leg members,respectively, for movement relative thereto and first and second rollersmounted on opposite ends of said second support leg members,respectively, said first rollers being engageable with the ground forsupporting said ramp and said second rollers being engageable withrespective cam means on said second ramp section for causing said secondsupport leg members to move slidably in and with respect to said firstsupport leg members, respectively, to support said ramp by said firstrollers.
 13. The ramp set forth in claim 12 including: support pinmembers mounted on said first support leg members and extending throughelongated slots in said second support leg members, respectively, forsupporting said second support leg members for limited movement withrespect to said first support leg members.